Photodynamic therapy simplified: nonprepared, moderate‐grade actinic keratosis lesions respond equally well to 5‐aminolaevulinic acid patch photodynamic therapy as do mild lesions. (1st November 2015) - Szeimies, R.M.; Hauschild, A.; Ortland, C.; Moor, A.C.E.; Stocker, M.; Surber, C.